--- /dev/null
+<?php
+
+namespace Drupal\tracker\Plugin\views\argument;
+
+use Drupal\comment\Plugin\views\argument\UserUid as CommentUserUid;
+
+/**
+ * UID argument to check for nodes that user posted or commented on.
+ *
+ * @ingroup views_argument_handlers
+ *
+ * @ViewsArgument("tracker_user_uid")
+ */
+class UserUid extends CommentUserUid {
+
+ /**
+ * {@inheritdoc}
+ */
+ public function query($group_by = FALSE) {
+ // Because this handler thinks it's an argument for a field on the {node}
+ // table, we need to make sure {tracker_user} is JOINed and use its alias
+ // for the WHERE clause.
+ $tracker_user_alias = $this->query->ensureTable('tracker_user');
+ $this->query->addWhere(0, "$tracker_user_alias.uid", $this->argument);
+ }
+
+}